Cuprous Oxide is the inorganic oxide.
Definition
US FDA substance register · UNII T8BEA5064F · registered name Cuprous oxide · single chemical substance
Cuprous Oxide is the inorganic oxide. See "Regulatory and Ingredient Use Information," for Colorants in Volume 1, Introduction, Part A.
Cosmetic roles
Safety & regulatory references
Korea’s toxic-substance GHS classification: Warning · H302 (category 4) · H332 (category 4) · H319 (category 2) · +2 more
More data — names, identifiers, properties, test records, literature
Names & identifiers
- CAS No.chemical registry number
- 1317-39-1
- EC No.EU chemical inventory number
- 215-270-7
- DTXSIDUS EPA chemical ID
- DTXSID0034489
- DTXCIDUS EPA compound ID
- DTXCID401324398
- IUPAC
- Dicopper(1+) oxide
- Molecular formula
- Cu2O
- Molecular weight
- 143.091 g/mol
Measured properties
- Appearance
- Other Solid, Dry Powder, CBI, Large Crystals · Yellow, red, or brown solid, Practically insoluble in water, [Merck Index] Dark red powder, [Sigma-Aldrich MSDS]
- Boiling point
- Decomp at 1800 °C
- Melting point
- 1235 °C · 1232 °C
- Solubility
- Crimson, scarlet, vermilion, deep or brownish-red, secondary mineral, adamantine or dull luster, brownish red streak, sol in nitric and concentrated hydrochloric acids, specific gravity: 5.85-6.15, Mohs hardness: 3.5-4 /Cuprite/ · Soluble in ammonium hydroxide, in hydrochloric acid forming copper(I) chloride which dissolves in excess hydrochloric acid, with dil sulfuric acid or dil nitric acid the cupric salt is formed and half copper is pptd as the metal.
- Density
- 6.0 · Relative density (water = 1): 6.0
- Stability
- STABLE, LIABLE TO OXIDATION TO CUPRIC OXIDE AND TO CONVERSION TO A CARBONATE ON EXPOSURE TO MOIST AIR. · STABLE IN DRY AIR.
- Odour
- odourless
- Melting/freezing point
- &, gt, 673 K
- Water solubility
- 28.6 g/ℓ (20℃, pH: 4)
- Vapour density
- 5870 ㎏/㎥ (20℃)
- Relative density
- 5.87
- Decomposition temperature
- 1800 ℃
- Molecular weight
- 143.09
Values measured on the substance itself. The KOSHA data are a reference for writing and reviewing safety data sheets, not a specification for a commercial raw material.
Source: PubChem · KOSHA safety data sheets (Korea)
What products actually use it for
What the 10 products reported to the US EPA with this ingredient use it for. Products outside cosmetics are included, so the top few rows are its main uses.
- Biocide3
- Soil amendments2
- Alloying element2
- Softener and conditioner1
- Processing aids not otherwise specified1
- Surfactant (surface active agent)1
Source: US EPA CompTox dashboard
Irritation and sensitisation studies
4 skin studies and 6 eye studies are on record.
The study conclusions largely agree (100%). These tests are on the raw material itself; irritation at the amount in a finished product is a different question.
See all 10 studies
- Classification not possible
Skin Sensitization · Screening - Not classified
Skin Irritation · Screening - Not likely to be sensitizing
skin sensitisation: in vivo (non-LLNA) · Screening · according to OECD Guideline 406 (Skin Sensitisation) - Studies Indicate No Significant Irritation
skin irritation: in vivo · Screening · OECD Guideline 404 (Acute Dermal Irritation / Corrosion) according to - Category 6.4A (Category 2A)
Eye Irritation · Read Across - Eye Dam. 1
Eye Irritation · Authoritative - Studies Indicate No Significant Irritation
eye irritation: in vivo · Screening · OECD Guideline 405 (Acute Eye Irritation / Corrosion) according to - Category 2
Eye Irritation · Screening - Studies Indicate No Significant Irritation
eye irritation: in vivo · Screening · EPA OPP 81-4 (Acute Eye Irritation) according to OECD Guideline 405 (Acute Eye Irritation / Corrosion) equivalent or similar to - Severe Irritation
eye irritation: in vivo · Screening · OECD Guideline 405 (Acute Eye Irritation / Corrosion) according to
Source: US EPA CompTox dashboard
Related literature
- Fundamental Insights into Copper-Epoxy Interfaces for High-Frequency Chip-to-Chip Interconnects · 2024
- Hierarchical Quaternized Cuprous Oxide: A Single-Component Hybrid for Synergistic Antibacterial Surfaces and Accelerated WoundHealing. · 2026
- Robust, conformal Cu2O coatings on polypropylene fabrics via atmospheric-pressure spatial atomic layer deposition · 2026
- Biocidal activity of multifunctional cuprite-doped anion exchanger - Influence of bacteria type and medium composition. · 2023
- Transparent Anti-SARS COV-2 Film from Copper(I) Oxide Incorporated in Zeolite Nanoparticles. · 2022
Linked databases 17
- Australian Industrial Chemicals Inventory (AICIS)
- ChEBI
- EU CosIng ingredient list 2
- Korea Cosmetic Association ingredient dictionary
- Korea toxic substances GHS register (NIER)
- KOSHA safety data sheets (Korea)
- MFDS (Korea) cosmetic ingredient register 2
- NIST Chemistry WebBook
- PubChem
- Tlooto literature search 2 3 4 5
- UniChem cross-reference IDs
- US EPA CompTox dashboard 2
- US EPA DSSTox chemical database
- US FDA substance registration (GSRS)
- US FDA Unique Ingredient Identifier (UNII)
- Wikidata
- Wikipedia · Korean · English · Japanese · Chinese